Splitting of a Solid Using Conversion of Material

ABSTRACT

The invention relates to a method for creating a detachment zone (2) in a solid (1) in order to detach a solid portion (12), especially a solid layer (12), from the solid (1), said solid portion (12) that is to be detached being thinner than the solid from which the solid portion (12) has been removed. The method according to the invention preferably comprises at least the steps of: providing a solid (1) which is to be processed and which is made of a chemical compound; providing a LASER light source; and subjecting the solid (1) to LASER radiation from the LASER light source so that the laser beams penetrate into the solid (1) via a surface of the solid portion (12) that is to be cut off; the LASER radiation controlling the temperature of a predefined portion of the solid (1) inside the solid (1) in a defined manner such that a detachment zone (2) or a plurality of partial detachment zones (25, 27, 28, 29) is formed; characterized in that the temperature produced by the laser beams in a predefined portion of the solid (1) is so high that the material forming the predefined portion is subject to modifications (9) in the form of a predetermined conversion of material.

According to claim 1, the invention at hand relates to a method forcreating a detachment zone in a solid in order to detach a solid portionfrom the solid and, according to claim 13, to a method for detaching atleast one solid portion from a solid.

The splitting of solids, in particular of wafers, is classicallyeffected by means of sawing. This splitting method, however, has aplurality of disadvantages. For instance, chips are always createdduring sawing, which thus represent destroyed basic material. Thethickness fluctuation of the sawed-off disks further also increases whenthe sawing height increases. In addition, the sawing element has theeffect that grooves and surface damages are created on the surfaces ofthe disks, which are to be separated from one another.

It can thus be seen that the splitting method “sawing” involves veryhigh material costs and costs for the reworking.

Publication WO 2013/126927 A2 further discloses a method for cutting offdevice layers from an original wafer. According to WO 2013/126927 A2,the overall arrangement is thereby heated up very strongly as a resultof a laser application. This heating is required in order to reachstresses in the interior of the solid via the different heat expansioncoefficients of the solid material and via a “handler”. It can be seenhereby that the thermal stressability of the “handler” must be veryhigh, because very high temperatures appear. According to WO 2013/126927A2, the laser beams are further always introduced into the solid via asurface, which is not part of the layer to be separated. This also leadsto a strong heating of the solid. The high temperatures also have thedisadvantage that the solid distorts or expands unintentionally, wherebythe generation of crystal lattice modifications is only possible in ahighly inaccurate manner.

According to WO 2013/126927 A2, thick and large solids can thus not beprocessed.

It is thus the object of the invention at hand to provide an alternativemethod for cutting off solid portions, in particular a plurality ofsolid layers, from a solid. According to the invention, theabove-mentioned object is solved by means of a method for creating adetachment zone in a solid in order to detach a solid portion,especially a solid layer, from the solid, wherein the solid portion,which is to be detached, is thinner than the solid, from which the solidportion has been removed. According to the invention, the methodcomprises at least the steps of providing a solid, which is to beprocessed, wherein the solid is made of a chemical compound; providing aLASER light source or a laser radiation source, respectively; applyingLASER radiation from the LASER light source to the solid, wherein thelaser beams penetrate into the solid via a surface of the sold portion,which his to be cut off, wherein the LASER radiation controls thetemperature of a predefined portion of the solid inside the solid in adefined manner such that a detachment zone or a plurality of partialdetachment zones is formed. Particularly preferably, the temperatureproduced by the laser beams in the predefined portion of the solid is sohigh, in particular more than 200° C. or more than 500° C. or more than800° C. or more than 1000° C. or more than 1500° C. or more than 2000°C., that the material forming the predefined portion is subject tomodifications in the form of a predetermined conversion of material.

This solution is advantageous, because a material conversion or phaseconversion, respectively, can preferably be effected without a localdestruction of the crystal lattice, whereby a weakening or stabilityreduction, respectively, can be created in the solid in a highlycontrolled manner.

Further preferred embodiments are the subject matter of the subclaimsand of the following description parts.

According to a further preferred embodiment of the invention at hand,the material conversion represents a decomposition of the chemicalcompound into a plurality or into all individual components or elements,respectively. This embodiment is advantageous, because the materialcombination, which is most suitable for cutting off the solid portion,can be adjusted in a defined manner by means of the systematicdecomposition of the chemical compound of the solid.

According to the description at hand, a solid starting material ispreferably understood as a monocrystalline, polycrystalline or amorphousmaterial. Preferably, monocrystallines comprising a highly anisotropicstructure are suitable because of the highly anisotropic atomic bindingforces. The solid starting material preferably has a material or amaterial combination from one of the main groups 3, 4, 5 and/or thesubgroup 12 of the periodic table of elements, in particular acombination of elements from the 3., 4., 5. main group and the subgroup12, such as, e.g. zinc oxide or cadmium telluride.

in addition to silicon carbide, the semiconductor starting material canfor example also consist of silicon, gallium arsenide GaAs, galliumnitride GaN, silicon carbide SiC, indium phosphide InP, zinc oxide, ZnO,aluminum nitride AlN, germanium, gallium(III) oxide Ga2O3, aluminumoxide Al2O3 (sapphire), gallium phosphide GaP, indium arsenide InAs,indium nitride InN, aluminum arsenide AlAs or diamond.

The solid or the workpiece (e.g. wafer), respectively, preferably has amaterial or a material combination from one of the main groups 3, 4 and5 of the periodic table of elements, such as, e.g., SiC, Si, SiGe, Ge,GaAs, InP, GaN, Al2O3 (sapphire), AlN. Particularly preferably, thesolid has a combination of elements from the fourth, third and fifthgroup of the periodic table. Possible materials or material combinationsare thereby e.g. gallium arsenide, silicon, silicon carbide, etc. Thesolid can furthermore have a ceramic (e.g. Al2O3—aluminum oxide) or canconsist of a ceramic, preferred ceramics are thereby, e.g., perovskiteceramics (such as, e.g., Pb-, O-, Ti/Zr-containing ceramics) in generaland specifically lead-magnesium-niobate, barium titanate, lithiumtitanate, yttrium-aluminum-garnet, in particular yttrium-aluminum-garnetcrystals for solid laser applications, SAW ceramics (surface acousticwave), such as, e.g., lithium niobate, gallium orthophosphate, quartz,calcium titanate, etc. The solid thus preferably has a semiconductormaterial or a ceramic material or the solid particularly preferablyconsists of at least one semiconductor material or a ceramic material,respectively. Preferably, the solid is an ingot or a wafer. Particularlypreferably, the solid is a material, which is at least partiallytransparent for laser beams. It is thus furthermore conceivable for thesolid to have a transparent material or to partially consist of or bemade of, respectively, a transparent material, such as, e.g. sapphire.Further materials, which are hereby possible as solid material alone orin combination with another material, are, e.g., “wide band gap”materials, InAlSb, high-temperature superconductors, in particular rareearths cuprate (e.g. YBa2Cu3O7). In addition or in the alternative, itis conceivable for she solid to be a photomask, wherein every photomaskmaterial known on the filing date and particularly preferablycombinations thereof can be used as photomask material in the case athand. In addition or in the alternative, the solid can further havesilicon carbide (SiC) or can consist thereof. Preferably, the solid isan ingot, which, in an initial state, i.e. in a state prior to cuttingoff the first solid portion, preferably weighs more than 5 kg or morethan 10 kg or more than 15 kg or more than 20 kg or more than 25 kg ormore than 30 kg or more than 35 kg or more than 50 kg. The solid portionis preferably a solid layer, in particular a wafer with a diameter of atleast 300 mm.

According to a further preferred embodiment of the invention at hand,the LASER radiation is introduced into the solid with a pulse density ofbetween 100 nJ/μm² and 10000 nJ/μm², preferably between 200 nJ/μm² and2000 nJ/μm² and particularly preferably between 500 nJ/μm² and 1000nJ/μm² for controlling the temperature in a defined manner.

According to a further preferred embodiment of the invention at hand,the receiving layer has a polymer or consists thereof, wherein thepolymer is preferably polydimethylsiloxane (PDMS) or an elastomer or anepoxy resin or a combination thereof.

According to a further preferred embodiment of the invention at hand,the energy of the laser beam of the laser, in particular fs laser(femtosecond laser) is chosen in such a way that the material conversionin the solid or in the crystal, respectively, in at least one directionis smaller or larger than 30-times, or 20-times, or 10-times or 5-timesor three-times the Rayleigh length.

According to a further preferred embodiment of the invention at hand,the wavelength of the laser beam of the laser, in particular of the fslaser, is chosen in such a way that the linear absorption of the solidor of the material, respectively, is less than 10 cm⁻¹ and preferablyless than 1 cm⁻¹ and particularly preferably less than 0.1 cm⁻¹.

According to a further preferred embodiment of the invention at hand,the solid is connected to a cooling device via a solid surface, whereinthe solid surface, which is connected to the cooling device, is embodiedparallel or substantially parallel to the surface, via which the laserbeams penetrate into the solid, wherein the cooling device is operatedas a function of the laser application, in particular as a function ofthe temperature control of the solid, which results from the laserapplication. Particularly preferably, the surface, via which the solidis connected to the cooling device, is located exactly opposite thesurface, via which the laser beams penetrate into the solid. Thisembodiment is advantageous, because a temperature increase of the solid,which occurs in response to the generation of the modifications, can belimited or reduced. The cooling device is preferably operated in such away that the heat input introduced into the solid by means of the laserbeams is removed from the solid through the cooling device. This isadvantageous, because the occurrence of thermally induced stresses ordeformations can be reduced significantly through this.

According to a further preferred embodiment of the invention at hand,the cooling device has at least one sensor device for capturing thetemperature of the solid and, as a function of a predefined temperaturecourse, effects a cool-down of the solid. This embodiment isadvantageous, because a temperature change of the solid can be capturedin a highly accurate manner by means of the sensor device. The change ofthe temperature is preferably used as data input for controlling thecooling device.

According to a further preferred embodiment of the invention at hand,the cooling device is coupled to a rotating means and the cooling devicecomprising the solid arranged thereon is rotated by means of therotating means during the generation of the modifications, in particularwith more than 100 revolutions per minute or with more than 200revolutions per minute or with more than 500 revolutions.

According to a further preferred embodiment of the invention at hand,the number of the generated modifications per cm² is different in atleast two different zones of the solid, wherein a first block ofmodifications is generated in a first zone, wherein the individualmodifications per line are preferably generated spaced apart from oneanother by less than 10 μm, in particular less than 5 μm or less than 3μm or less than 1 μm or less than 0.5 μm, and the individual lines ofthe first block are generated spaced apart from one another by less than20 μm, in particular less than 15 μm or less than 10 μm or less than 5μm or less than 1 μm, wherein a first partial detachment zone is formedby the first block of modifications and a second block of modificationlines is generated in a second zone, wherein the individualmodifications per line are preferably generated spaced apart from oneanother by less than 10 μm, in particular less than 5 μm or less than 5μm or less than 1 μm, or less than 0.5 μm, and the individual lines ofthe second block are generated spaced apart from one another by lessthan 20 μm, in particular less than 15 μm or less than 10 μm or lessthan 5 μm or less than 1 μm, wherein a second partial detachment zone isformed by the second block of modifications, wherein the first zone andthe second zone are spaced apart from one another by a third zone,wherein no modifications or essentially no modifications are generatedin the third zone by means of laser beams, and the first zone is spacedapart from the second zone by more than 20 μm, in particular more than50 μm or more than 100 μm or more than 150 μm or more than 200 μm. Thisembodiment is advantageous, because mechanical stresses, which are solarge that either a local cracking of the solid can take place or that acrack is created in the solid as a result of a further triggering event,such as the thermal application of a receiving layer arranged on thesolid, can be created in the solid by means of the local generation ofmodification blocks. It has been recognized that the modification blockshave the effect that a tear is also guided in a stable manner in a zonebetween two modification blocks. Thanks to the modification blocks, acontrolled and highly accurate crack propagation can be effected bymeans of fewer modifications. This has significant advantages, becausethe processing time is shortened, the energy consumption is reduced, andthe heating of the solid is reduced.

The modifications in the first block are preferably generated at pulseintervals of between 0.01 μm and 10 μm and/or line spacings of between0.01 μm and 20 μm are provided, and/or a pulse repetition frequency ofbetween 16 kHz and 20 KHz is provided.

According to a further aspect of the invention at hand, an optics, bymeans of which the laser beams are guided from a laser beam source tothe solid, is adapted as a function of the location, at which amodification is generated, from which at least one change of thenumerical aperture is effected, wherein the numerical aperture at alocation in the edge zone of the solid is smaller than at a differentlocation of the solid, which is located closer to the center of thesolid. This embodiment is advantageous, because modifications comprisingdifferent properties are generated. In particular in the edge zone, i.e.in the zone of up to 10 mm or of up to 5 mm or of up to 1 mm (in radialdirection) away from the edge, an optics is preferably used, which is anumerical aperture of between 0.05 and 0.3, in particular ofsubstantially or of exactly 0.1. For the remaining zones, an optics ispreferably used, in the case of which the numerical aperture is between0.2 and 0.6, preferably between 0.3 and 0.5, and particularly preferablyis substantially or exactly 0.4.

According to a further preferred embodiment of the invention at hand,the thermal application of the receiving layer comprises a cool-down ofthe receiving layer to a temperature of below 20° C., in Particularbelow 10° C. or below 0° C. or below −10° C. or below 100° C. or to orbelow the glass transition temperature of the material of the receivinglayer.

By means of the temperature control, modifications are or the materialconversion is generated by means of LASER, wherein the pulse intervalsare provided between 0.01 μm and 10 μm, in particular with 0.2 μm, and;or line spacings of between 0.01 μm and 20 μm, in particular with 3 μm,and/or a pulse repetition frequency of between 16 kHz and 20 MHz, inparticular with 128 kHz, is provided, and/or a pulse energy of between100 nJ and 2000 nJ, in particular with 400 nJ, is provided. Particularlypreferably, a pikosecond or femtosecond laser is used for the methodaccording to the invention, in particular when applying silicon carbide,wherein the LASER preferably has a wavelength of between 800 nm and 1200nm, in particular of 1030 nm or 1060 nm. The pulse duration ispreferably between 100 fs and 1000 fs, in particular at 300 fs.Preferably, a lens for focusing the laser beam is furthermore used,wherein the lens preferably effects a 20-100-times reduction, inparticular a 50-times reduction or focusing, respectively, of the LASERbeam. Preferably, the optics for focusing the laser beam furthermore hasa numerical aperture of between 0.1 and 0.9, in particular of 0.65.

Preferably, every material conversion effected by means of the LASERradiation represents a modification of the material of the solid,wherein the modifications can additionally or in the alternative beunderstood as destruction of the crystal lattice of the solid, e.g.According to a further preferred embodiment of the invention at hand,the solid is moved with respect to the LASER light source, in particulardisplaced, in particular rotated. The movement, in particular rotation,of the solid with respect to the LASER light source preferably takesplace in a continuous manner. The rotational speeds appearing therebypreferably exceed 1 revolution per second or 5 revolutions per second or10 revolutions per second or a linear speed of at least 100 mm/s,respectively. For this purpose, the solid is preferably arranged on arotary table or rotary chuck, respectively, in particular by means ofadhesion. The number of modification per cm² of the solid surface,through which the LASER radiation penetrates into the solid in order togenerate the modifications, per rotation is preferably below apredefined maximum number, wherein the maximum number of themodifications per cm² and per rotation is preferably determined as afunction of the solid material and/or of the energy density of the LASERradiation and/or as a function of the duration of the LASER radiationimpulses. Preferably, a control device is provided, which determines themaximum number of the modifications to be generated per cm² per rotationas a function of at least two or three or all of the above-mentionedparameters and preferably of further parameters by means of predefineddata and/or functions. This is especially advantageous, because it wasrecognized that damaging vertical cracks are created, when the damagedensity is too high, which results from stresses, which are createdbetween the processed zones and the zones, which have not been processedyet.

In addition or in the alternative, the modifications are generated withdifferent patterns, in particular distances between the individualnewly-generated modifications and/or with changed energy input, inparticular reduced energy input, in response to consecutive rotations ofthe solid with respect to the LASER light source. Either the laser orthe wafer or solid, respectively, can in particular be displaced in XYdirection, wherein the modifications are generated as a function of thetranslational XY displacement. According to a preferred embodiment, anXY table is used, on which the solid is arranged during the operation ofthe laser. The optics, by means of which the LASER beams are deflected,is preferably readjusted or newly adjusted, respectively, continuouslyor in stages, in particular as a function of a movement of the solid, inparticular of a rotation of the solid, by means of the already mentionedcontrol device or an alternative control device. Due to the readjustmentor new adjustment, respectively, an adjustment of a second LASER beamcourse preferably takes place with respect to the first LASER beamcourse, which is adjusted prior to the readjustment or new adjustment,respectively, which differs from the first LASER beam course. As afunction of the rotation of the solid, the control device thuspreferably adjusts different LASER beam courses. Particularlypreferably, the LASER scanning direction is thereby in each casereadjusted or newly adjusted, respectively, or changed, respectively. Inaddition or in the alternative, the control device preferably controlsthe LASER light source, the optics, in particular the scanners, and/orthe device, which displaces the solid, in particular the rotary table orrotary chuck, respectively, in such a way that the energy input, perrotation remains the same or decreases, wherein the energy input intothe solid preferably decreases continuously, i.e. with each rotation, ordecreases in stages, i.e. in each case after a plurality of rotations.Wherein the number of rotations per stage can differ from one another inthe case of a gradual decrease of the energy input, a first stage cancomprise more than 2 rotations, e.g., and another stage can comprisemore or fewer rotations than the first stage. It is furthermoreconceivable that the stages in each case comprise the same number ofrotations. The stage method can further also be mixed or combined,respectively, with the continuous method.

According to a preferred embodiment, the laser beam can also repeatedlyapply modifications to a line, so that a total modification is generatedin a line or row, respectively. According to a further alternative, thelines can cross or overlap one another, respectively, when applyingmodifications to the laser, wherein the first line of the modificationscan in particular intersect one another at a predetermined angle of forexample 90°, 45°, 30°, 60° or at another freely selectable angle. Theintersecting angles between lines of the laser application forgenerating modifications can thereby orientate themselves on the crystalorientation of the material of the solid, in order to increase theeffectiveness of the added modifications.

In addition or in the alternative, the LASER light source embodied asscanner and the generation of the modifications takes place a functionof the laser scanning direction, the laser polarization direction andthe crystal orientation. The devices required for generatingmodifications, in particular the LASER light source, the optics, inparticular the scanner, and the device, which displaces the solid, inparticular the rotary table or rotary chuck, respectively, is preferablycontrolled by means of the already mentioned control device or by meansof an alternative control device, which, as a function of at least twoor three of the above-mentioned parameters and preferably furtherparameters, by means of predefined data and/or functions.

In addition or in the alternative, the distance between the centers oftwo modifications, which are generated consecutively in modificationgenerating direction or in circumferential direction of the solid, isless than 10000 nm, in particular less than 1000 nm, in particular lessthan 100 nm.

In addition or in the alternative, the outer limitations ofmodifications, which are generated consecutively in modificationgenerating direction or in circumferential direction of the solid, arespaced apart from one another by less than 10000 nm, in particular lessthan 1000 nm, in particular less than 100 nm.

The invention at hand can further refer to a method for creating adetachment zone in a solid in order to detach a solid portion from thesolid, which comprises at least the below-mentioned steps of:

providing a solid, which is to be processed, providing a LASER lightsource, applying LASER radiation from the LASER light source to thesolid, wherein the LASER radiation generates modifications, inparticular crystal lattice defects, in the solid, wherein a controldevice for controlling the LASER light source and/or a device, whichdisplaces the solid, in particular a rotary table or rotary chuck,respectively, and/or an optics, in particular a scanner, as a functionof individual or a plurality of certain parameters or as function ofindividual or plurality of these parameters is provided.

The solid is preferably rotated with respect to the LASER light sourceand the number of the modifications per cm² of the solid surface perrotation, through which the LASER radiation penetrates into the solid inorder to generate the modifications, is below a predefined maximumnumber, wherein the maximum number of the modifications per cm² and perrotation is preferably determined as a function of the solid materialand of the energy density of the LASER radiation, and/or themodifications are generated with different patterns, in particulardistances between the individual newly generated modifications and/orwith changed energy input, in particular reduced energy input, inresponse to consecutive rotations of the solid with respect to the LASERlight source, and/or the LASER light source is embodied as scanner andthe generation of the modifications takes place as a function of thelaser scanning direction, the laser polarization direction and thecrystal orientation, and/or the distance between the centers of twomodifications, which are generated consecutively in modificationgenerating direction or in circumferential direction of the solid isless than 10000 nm, in particular less than 1000 nm, in particular lessthan 100 nm,

and/or the outer limitations of modifications, which are generatedconsecutively in modification generating direction or in circumferentialdirection of the solid, are spaced apart from one another by less than10000 nm, in particular less than 1000 nm, in particular less than 100nm.

Preferably, the maximally possible number of the modifications, whichcan be generated in one displacement cycle, in particular one rotation,of the solid with respect to the optics, in particular a scanner, isdetermined by a plurality of parallel lines, which are in particularspaced apart from one another in radial direction, and themodifications, which can be maximally generated per line. According to apreferred embodiment, the laser beam can be divided into a plurality oflaser beams by means of a diffractive optical element, in order to thussimultaneously generate a corresponding number of modificationsaccording to the splitting of the laser beam. The plurality of the linespreferably comprises at least two and preferably at least 10 andparticularly preferably up to 50 or up to 100 or up to 200 lines. Withregard to the generated patterns, it is conceivable thereby that in thecase of a certain number of lines in a first displacement cycle, e.g.only every x^(th) line or every x^(th) and y^(th) line or every x^(th)and every x^(th) minus z line is provided with modifications.Concretely, every 5^(th) line, for example, could be provided withmodifications. In the alternative, every 5^(th) and every 7^(th) linecould be provided with modifications. In the alternative, e.g., every5^(th) and every 5^(th) minus 2 could be provided with modifications,which would then result in that the 3^(rd), 5^(th), 8^(th), 10^(th)13^(th), 15^(th), etc. line is provided with modifications. In addition,it is possible that the modifications are generated block by block, thatis, that for example a block of 50 consecutive lines includes amodification and the following 50 lines do not include any modificationsat all, wherein this block of 50 lines without modification is in turnfollowed by a block of 50 lines comprising a modification. This meansthat block by block modifications of a plurality of lines are providedalternately. According to a further embodiment, the width of suchalternating blocks can vary according to the distance from the edge ofthe sample, that is that the blocks have a smaller line number ofmodifications for example in the area of the edge, and have a higherline number of modifications towards the center of the sample. It isconceivable in addition or in the alternative that the distance betweenthe lines, in which modifications are generated, change as a function ofa function. In a second displacement cycle, which preferably appearsafter the end of the first displacement cycle, in particular after afirst rotation, alternative lines, which are preferably spaced apartrelative to one another, are preferably written. In the seconddisplacement cycle and in the further displacement cycles, other linenumbers can then be provided for the variables x, y, z. More or fewervariables can further be provided. In addition or in the alternative,the distance between the individual modifications of a line can begenerated according to a pattern. The modifications in one line are thuspreferably generated in a first displacement cycle, in particular afirst rotation, e.g. only at every a^(th) point (at which a modificationis provided) or at every a^(th) and b^(th) point or at every a^(th) andevery a^(th) minus c point. In addition or in the alternative, it isconceivable that the distance between the points, at which modificationsare generated, changes as a function of a function. In a seconddisplacement cycle, which preferably appears after the end of the firstdisplacement cycle, in particular after a first rotation, alternativepoints, which are preferably spaced apart relative to one another, arepreferably written. In the second displacement cycle and in the furtherdisplacement cycles, other line numbers can then be provided for thevariables a, b, c. In addition or in the alternative, it is conceivablethat the lines, which are processed, are determined at least as afunction of a displacement point or displacement setting, respectively,in particular a rotational position, and the number of rotations and/orthe points in a line, which are processed (or at which modifications aregenerated, respectively) are determined at least as a function of thedisplacement position or displacement point, in particular a rotationalposition, and the number of rotations. In particular in the case oflinear displacement paths of the solid or of the optics, lines or stripsof modifications, which are positioned at an incline to one another, inparticular at a right angle, can be generated as well.

According to a further preferred embodiment, every material conversion,which is effected by means of the LASER radiation, represents amodification of the material of the solid, wherein the solid is moved ina translational manner in XY direction with respect to the LASER lightsource, and the number of modifications per cm² of the solid surface,through which the LASER radiation penetrates into the solid in order togenerate the modifications, wherein the maximum number of themodifications per cm² and according to the translational movement in XYdirection is preferably determined as a function of the solid materialand of the energy density of the LASER radiation and/or themodifications are generated with different patterns, in particulardistances between the individual newly generated modifications, and/orwith changed energy input, in particular reduced energy input, accordingto the translational movement in XY direction of the solid with respectto the LASER light source, and/or the LASER light source is embodied asscanner, and the generation of the modifications takes place as afunction of the laser scanning direction, the laser polarizationdirection and the crystal orientation, and/or the distance between thedisplacements of two modifications, which are generated consecutively inmodification generating direction is less than 10000 nm, in particularless than 1000 nm, in particular less than 100 nm, and/or the outerlimitations of modifications, which are generated consecutively inmodification generating direction, are spaced apart from one another byless than 10000 nm, in particular less than 1000 nm, in particular lessthan 100 nm.

According to a further preferred embodiment, the LASER radiationgenerates modifications, in particular crystal lattice effects, in thesolid, wherein the solid is moved in a translational manner with respectto the LASER light source, and the number of the modifications per cm²of the solid surface, through which the LASER radiation penetrates intothe solid in order to generate the modifications, wherein the maximumnumber of the modifications per cm² and according to the translationalmovement in XY direction is preferably determined as a function of thesolid material and of the energy density of the LASER radiation and/orthe modifications are generated with different patterns, in particulardistances between the individual newly generated modifications, and/orwith changed energy input, in particular reduced energy input, accordingto the translational movement in XY direction of the solid with respectto the LASER light source, and/or the LASER light source is embodied asscanner, and the generation of the modifications takes place as afunction of the laser scanning direction, the laser polarizationdirection and the crystal orientation, and/or the distance between thedisplacements of two modifications, which are generated consecutively inmodification generating direction is less than 10000 nm, in particularless than 1000 nm, in particular less than 100 nm, and/or the outerlimitations of modifications, which are generated consecutively inmodification generating direction, are spaced apart from one another byless than 10000 nm, particular less than 1000 nm, in particular lessthan 100 nm.

The control unit controls the generation of the modifications, forexample as a function of the number of the displacement cycles and/or ofthe local heat development, which is preferably captured opticallyand/or by means of sensors, and/or as a function of the materialproperties, in particular the density and/or the stability and/or thethermal conductivity of the solid. The invention further relates to amethod for cutting off at least one solid portion from a solid, inparticular a wafer, at least comprising the steps of: arranging areceiving layer on a solid, which is treated according to a methodaccording to one of claims 1 to 4, thermal application of the receivinglayer for, in particular mechanically, generating crack expansionstresses in the solid, wherein a crack expands in the solid along thedetachment zone due to the crack expansion stresses.

Further advantages, goals and characteristics of the invention at handwill be explained by means of the following description of attacheddrawings, in which the separating method according to the invention isillustrated in an exemplary manner. Components or elements, which arepreferably used in the method according to the invention, and/or whichat least substantially correspond in the figures with regard to theirfunction, can hereby be identified with the same reference numerals,wherein these components or elements do not need to be numbered orexplained in all figures.

FIG. 1 shows a schematic illustration of the laser-based generationaccording to the invention of a detachment layer in a solid;

FIG. 2 shows a schematic illustration of a preferred cut-off process forcutting off a solid layer from a solid 7;

FIG. 3 shows two microscopic illustrations of the surfaces, which werecreated along the detachment zone, of the solid portions, which are cutoff from one another;

FIG. 4 shows an illustration for showing the effect according to theinvention;

FIGS. 5a-5c show three schematic cross sectional illustrations, which ineach case show modification blocks in a solid;

FIGS. 5d-5e show two schematic illustrations, in each case along thedetachment zones of split solids, wherein the illustration according toFIG. 5d does not show any modification remainders and the illustrationaccording to FIG. 5e shows modification remainders;

FIGS. 6a-c show three schematic illustrations of modification blocks andthe local solid weakening or local solid cracks created through this;

FIGS. 7a-c show three schematic illustrations of exemplary crack paths;

FIGS. 8a-c show the repeated cut-off of solid portions or solid layers,respectively, in particular wafers, from a solid;

FIGS. 9a-f show a plurality of steps from the provision of the solid tothe triggering of the crack as a result of a thermal application of thereceiving layer;

FIG. 10a shows a schematic illustration of the state after the solidportion cut-off;

FIG. 10b shows a further laser application of the remaining solid forgenerating modifications for cutting off a further solid layer;

FIG. 10c shows a schematic illustration of the remaining solid arrangedon a cooling device, wherein the cooling device is arranged on adisplacement device, in particular a rotary table;

FIG. 10d shows a schematic illustration of the generation ofmodifications in the solid;

FIG. 11 shows a schematic illustration of a cooling device, inparticular of a cooling chuck;

FIG. 12 shows a schematic illustration of a preferably used optics; and

FIG. 13 shows a schematic illustration of overlapping beams or beamportions, respectively, in response to the generation of a modificationin the solid.

In FIG. 1, reference numeral 1 identifies the solid. According to theinvention, modifications 9 are generated in the solid 1, in order toform a detachment zone 2, at which or along which, respectively, thesolid 1 is separated into at least two components. The modifications 9are thereby material conversions or phase conversions, respectively, ofthe solid material, by means of which the detachment zone 2 is created.The modifications 9 are generated by means of at least one laser beam 4.The laser beam 4 penetrates into the preferably at least partiallytransparent solid 1 via a preferably treated, in particular polished,surface 5. On the surface 5, the at least one laser beam is preferablybroken, which is identified by reference numeral 6. The at least onelaser beam then forms a focus 8 for generating the modification. Thepolished surface 5 can also be identified as main surface 13.

FIG. 2 also shows the treated solid 1, wherein a receiving layer 140 forintroducing stresses into the solid 1, is arranged, in particularattached or generated, on at least one surface of the solid 1, inparticular partially or completely covering or overlapping the surface5. After splitting off the solid layer or the solid portion,respectively, from the solid 1, the receiving layer 140 initiallyremains on the split-off solid portion and thus serves to receive it.The receiving layer 140 preferably consists of a polymer material or hasa polymer material, in particular PDMS. Due to a temperature control, inparticular cool-down, of the receiving layer 140, the receiving layer140 contracts and thus introduces stresses into the solid 1, by means ofwhich a crack is triggered and/or is generated and/or guided for cuttingoff the solid portion from the solid 1.

The LASER application of the solid 1 particularly preferably representsa local temperature control of the solid 1, in particular in theinterior of the solid 1. Due to the temperature control, the chemicalbond of the solid material changes, whereby a change, in particularreduction, of the strength or stability, respectively, of the solid 1results in the applied portion. The LASER application preferably takesplace in a total plane, which penetrates in the solid 1, wherein it isalso conceivable for at least or maximally 30% or 50% or 60% or 70% or80% or 90% of the plane, which penetrates the solid 1, to experience themodification according to the invention.

Reference numeral 10 identifies a first solid portion after cuttingthrough the solid 1, and reference numeral 12 identifies the secondsolid portion after separating the solid 1. Reference numeral 11 furtheridentifies the surfaces, along which the two solid portions 10, 12 wereseparated from one another.

FIG. 3 shows a surface 11 of a first solid portion 10 and of a secondsolid portion 12, wherein the first solid portion 10 and the secondsolid portion 12 were separated from one another along the surfaces 11.FIG. 3 furthermore shows an untreated zone 51 or untreated portion ofthe solid 1, respectively, and a treated zone 52 or treated portion ofthe solid 1, respectively. The treated portion 52 was created by meansof the LASER application according to the invention and shows that thematerial of the solid 1 changed or was converted, respectively, in thiszone.

FIG. 4 shows a Raman spectrum (reference numeral 53) 6H—SiC withconditioning 1B after cutting off the solid portion 12. Referencenumeral 54 identifies the intensity in % and reference numeral 56identifies the wave number in cm⁻¹. Reference numeral 61 furthermoreidentifies the graph for the untreated material portion identified withreference numeral 51 in FIG. 3 and reference numeral 62 identified thegraph for the treated material portion identified with reference numeral52 in FIG. 3. It can be gathered from the Raman spectrum 53 that thematerial portions identified by reference numerals 51 and 52 havedifferent material properties, in particular are different materials.

The LASER application according to the invention effects amaterial-specific, spatially resolved cumulation of the entry input,from which a defined temperature control of the solid 1 results at adefined location or at defined locations and within a defined time. In aconcrete application, the solid 1 can consist of silicon carbide,whereby a locally highly limited temperature control of the solid 1 to atemperature of, e.g., more than 2830+/−40° C. is preferably carried out.New materials or phases, in particular crystalline and/or amorphousphases, result from this temperature control, wherein the resultingphases are preferably Si (silicon) and DLC (diamond-like carbon) phases,which are created with significantly reduced stability. The detachmentportion 2 then results from this stability-reduced layer. The lasercontrol preferably takes place by means of spatially resolved sampletemperature measurement in order to avoid edge effects in response tothe solid or wafer processing, respectively.

FIG. 5a shows that the number of the generated modifications per cm² isdifferent in at least two different zones of the solid 1. In a firstzone, a first block 91 is thereby generated at modification lines,wherein the individual modifications 9 per line are preferably generatedspaced apart from one another by less than 10 μm, in particular lessthan 5 μm or less than 3 μm or less than 1 μm or less than 0.5 μm. Theindividual lines of the first modification block 91 are preferablygenerated spaced apart from one another by less than 20 μm, inparticular less than 15 μm or less than 10 μm or less than 5 μm or lessthan 1 μm. Mechanical stresses are generated in the solid 1 by means ofthe first block 91 of modifications 91.

In a second zone, a second block 92 of modification lines is generated,wherein the individual modifications 9 per line are preferably generatedspaced apart from one another by less than 10 μm, in particular lessthan 5 μm or less than 3 μm or less than 1 μm or less than 0.5 μm. Theindividual lines of the second block 92 are preferably generated spacedapart from one another by less than 20 μm, in particular less than 15 μmor less than 10 μm or less than 5 μm or less than 1 μm. Mechanicalstresses are generated in the solid 1 by means of the second block 92 ofmodifications 92.

The first zone and the second zone are spaced apart from one another bya third zone, wherein no modifications or essentially no modifications 9are generated in the third zone by means of laser beams, and the firstzone is spaced apart from the second zone by more than 20 μm, inparticular more than 50 μm or more than 100 μm or more than 150 μm ormore than 200 μm.

The modifications 9 are hereby preferably introduced into the solid 1via a surface 5 of the subsequent solid layer 12. The distance betweenthe surface 5, via which the laser beams are introduced, to themodifications 9, is preferably less than the distance of themodifications 9 to a further surface 7 of the solid 1, which is spacedapart from the surface 5 and which is preferably oriented in parallel.

It can be seen that the detachment zone 2 according to this illustrationis located on one side, in particular below or above all modifications 9in solid longitudinal direction, and is preferably spaced apart from themodifications 9.

FIG. 5b show a similar basic construction. According to FIG. 5b , thedetachment zone 2, however, extends through the modifications 9.

FIG. 5c further shows that the detachment zone 2 can also run throughthe center of the modifications 9.

The course of the detachment zone 2 can hereby be adjusted via thenumber of the modifications 9 and/or the size of the modifications 9and/or the distance of the individual modifications 9 of a block 91, 92.

FIG. 5d shows the remaining solid 1 after the detachment of the solidlayer 12 along the detachment zone 2 shown in FIG. 5a . Due to the factthat the modifications 9 are completely removed from the remaining solid1 in this case, the remaining solid 1 does not show any remainders ofthese modifications 9.

In contrast, remainders of the modifications 9 can be gathered from FIG.5e . These modification remainders result, when the solid 1 is cut offalong a detachment zone 2, which is shown in FIG. 5b or 5 c. It canfurther be seen that the modification blocks 91, 92 are preferablyspaced apart from one another by cm2 each, preferably by means of fields901, 902, 903 without modifications or with fewer modifications,respectively. The fields without modifications 9 or with fewermodifications 9 can hereby preferably be smaller or larger than thezone, in which the modification blocks 91, 92 are created. At leastindividual, a plurality or the majority of the zones, in which themodification blocks 91, 92 are generated, are preferably many timeslarger, in particular at least 1.1-times or 1.5-times or 1.8-times or2-times or 2.5-times or 3-times or 4-times larger than the zones, inwhich no modifications 9 or fewer modifications 9 are generated.

FIGS. 6a-6c show a further embodiment of the invention at hand.According to these illustrations, the modification blocks 91, 92 serveto create local material weakening or local solid cracks or local stressincreases. Reference numeral 25 hereby identifies a first partialdetachment zone or crack portion, in which the local material weakeningor local solid cracks or local stress increases appear, and referencenumeral 27 hereby identifies a second partial detachment zone or crackportion, in which the local material weakening or local solid cracks orlocal stress increases appear as well. The individual partial detachmentzones or crack portions preferably form ends 71, 72, beyond which therespective partial detachment zone or crack portion can be enlarged. Theenlargement of the partial detachment zones or crack portions preferablytakes place as a result of a force introduction, which is effected bymeans of the receiving layer 140 (see FIG. 2).

FIGS. 7a to 7c show embodiments, according to which the course of thedetachment zone 2 is controlled in such a way as a result of thegeneration of the modification blocks 91, 92, 93 that predeterminedpatterns or thickness changes are created or compensated. The course ofthe detachment zone 2 can hereby be adjusted, e.g., via the number ofthe modifications 9 and/or the size of the modifications and/or thedistance of the individual modifications 9 of a block 91, 92, 93.

In FIG. 7a , the detachment zone 2 is formed by the below-mentionedcomponents: crack 31 between outer edge and first modification block 91,followed by the first crack portion 25, which is created directly bymeans of the first block 91 of modifications 9, follows by crack 32between the two modification blocks 91 and 92, followed by the secondcrack portion 27, which is created directly by means of the second block92 of modifications 9, followed by the crack 33 between the modificationblock 92 and the further outer edge of the solid 1. It can be seenthrough this that the detachment zone 2 can be predefined in such a waythat a crack for cutting off the solid layer 12 form the solid 1 can runat different planes in sections.

It can be seen according to FIG. 7b that the detachment zone 2 can bechosen in such a way that the course of the crack includes a pluralityof geometric turning points.

FIG. 7c shows a further possible design of the detachment zone 2 merelyin an exemplary manner.

With regard to FIGS. 7a-7c , it is important to note that the formationof wavy courses can offer advantages in response to the furthertreatment of the exposed surfaces, in particular in the case ofsubsequent grinding and/or polishing steps. Due to the height of themodifications 9, which is very small in fact, the actual waviness, whichis created via this, can only be captured in a high resolution. By meansof modification blocks, such as, e.g., the blocks 91, 92, 93, however,the crack can be guided in a very well-controlled manner, also in thezones, in which no or fewer modifications 9 are generated.

FIGS. 8a-8c show a repeated processing of a solid 1, in particular of aningot, wherein the solid 1 is in each case thinned by a solid portion12, especially a solid layer 12. Receiving layers 140, which may need tobe attached, as shown in FIG. 2, are not shown in these illustrations.In terms of the invention at hand, however, a receiving layer 140 forreceiving the solid portion 12 and for triggering and/or supporting acrack can also be arranged on the surface 5, 502, 504.

FIGS. 3a-8c thus in each case show the application of LASER radiationfrom the LASER light source to the solid, wherein the laser beamspenetrate into the solid 1 via a surface 5, 502, 504 of the solid layer12, which is to be cut off. The LASER radiation controls the temperatureof a predefined portion of the solid 1 inside the solid 1 in a definedmanner such that a detachment zone 2 or a plurality of partialdetachment zones are formed, the produced temperature in the predefinedportion of the solid 1 is thereby preferably so high that the materialforming the predefined portion is subject to modifications 9 in the formof a predetermined material conversion. The number and arrangement ofthe modifications 9 can thereby be adjusted and is preferablypredefined. After cutting off the solid portion 12, LASER radiation fromthe LASER source is again applied to the remaining solid 1, wherein theLASER radiation controls the temperature of a predefined portion of theremaining solid 1 inside the remaining solid 1 in a defined manner suchthat a detachment zone 2 is formed, and the temperature created in thepredefined portion of the remaining solid 1, in turn, is so high thatthe material, which forms the predefined portion, is subjected to apredetermined material conversion. Solid portions 12 of the same,similar or different thickness, e.g., in particular solid layers 12, inparticular wafers, can thus be cut off from a solid 1. The solid 1preferably has such a length that a plurality, in particular more than 2or more than 5 or more than 10 or more than 20 or more than 50 or morethan 100 or more than 150 or more than 200 solid layers 12 comprising athickness of less than 1000 μm, in particular of less than 800 μm or ofless than 500 μm or of less than 300 μm or of less than 200 μm or ofless than 150 μm or of less than 110 μm or of less than 75 μm or of lessthan 50 μm, can be cut off therefrom. A machining of the newly exposedsurface 502, 504 of the remaining solid 1 preferably takes place afterevery cut-off of a solid layer 12.

FIGS. 9a-9f show schematic illustrations of different processsituations, as they can occur according to the method according to theinvention for producing solid layers 12.

FIG. 9a shows the provision of the solid 1, in particular of an ingot.

According to FIG. 9b , the provided solid 1 is arranged on a coolingdevice 3. The cooling device 3 is preferably a cooling chuck.Particularly preferably, the solid 1 is coupled or adhered,respectively, or welded or screwed or clamped to a tool carrier (chuck),wherein the tool carrier preferably comprises a cooling functionalityand thus preferably becomes the cooling device 3. The tool carrierpreferably consists of an alloy comprising a composition of 45%-60%, inparticular 51% of iron, 20%-40%, in particular 29% of nickel and10%-30%, in particular 17% of cobalt. The percentages hereby refer tothe portion of the total mass. An example for a preferred cooling device3 is shown in FIG. 11. The solid 1 and the cooing device 3 preferablyhave the same or a similar thermal expansion, respectively. Everythermal expansion in response to a temperature increase of 10° C. in atemperature range of between −200° C. and 200° C. is hereby preferablyunderstood as similar thermal expansion, in the case of which thedifference of the thermal expansions of the solid 1 and of the coolingdevice 3 is less than 50%, in particular less than 25% or less than 10%of the thermal expansion of the object (cooling device of ingot), whichexpands most. The thermal expansion of the solid A is preferably lessthan 10 ppm/K, in particular less than 8 ppm/K or less than 5 ppm/K,such as, e.g., less than 4 ppm/K or substantially 4 ppm/K or exactly 4ppm/K.

The solid 1 is preferably fixed to the cooling device 3, in particularadhered, in longitudinal direction with its underside 7, which ispreferably located in longitudinal direction opposite to the surface 5.To generate the modifications 9, the laser beams are thus introducedinto the solid 1 via the surface 5, which is part of the solid layer 12to be cut off, in the direction of the cooling device 3.

FIG. 9c shows the generation of the modifications 9 by means of thelaser beams in a schematic manner. The cooling device 3 hereby effectsthat the energy or heat, respectively, introduced into the solid 1 bymeans of the laser beams, is at least partially and preferablypredominantly discharged from the solid 1.

FIG. 9d shows a schematic sectional illustration of the solid 1 afterthe generation of the modifications 9. According to this example, 4blocks of modifications 9 can be seen, which lead to the 4 crackportions 25, 27, 28, 29. Adjoining the blocks comprising modifications9, reference numerals 41, 42, 43, 44 and 45 in each case identify zoneswithout modifications 9, or zones, in which fewer modifications 9 aregenerated than in the zones, in which the blocks of modifications 9 aregenerated.

FIG. 9e shows a state, according to which a receiving layer 140, inparticular having a polymer material, is arranged or generated on thesurface 5, via which the laser beams have penetrated into the solid 1.The receiving layer 140 has preferably been created as film and has beenadhered to the surface 5 after its creation. It is also possible,however, to embody the receiving layer 140 by applying a liquid polymerto the surface 5 and by subsequent solidification.

FIG. 9f shows a temperature control of the receiving layer 140 in aschematic manner. The temperature of the receiving layer 140 ispreferably controlled, in particular cooled, to a temperature below theambient temperature, in particular to a temperature of less than 20′C,or of less than 1° C. or of less than 0° C. or of less than −10° C. orof less than −50′C or of less than −100° C. Wherein the material of thereceiving layer 140 is subjected to a glass transition as a result ofthe cool-down. The temperature of the receiving layer 140 is preferablycontrolled by means of liquid nitrogen. Due to the temperature control,in particular due to the glass transition, the receiving layer 140contracts, whereby mechanical stresses are created in the solid 1. Dueto the mechanical stresses, a crack, which connects the crack portions25, 27, 28, 29 and by means of which the solid portion 12 is cut offfrom the solid 1, is triggered.

FIG. 10a shows an illustration after the temperature control of thereceiving layer 140 shown in FIG. 9f . The solid portion 12 is cut offfrom the solid 1 by means of the receiving layer 140, which is stillarranged thereon.

FIG. 10b shows a new step of introducing modifications 9 into theremaining solid 1, which is reduced in its length by at least thealready cut-off solid layer 12.

FIG. 10c shows a further preferred design in a schematic manner. Thecooling device 3 is hereby coupled to the solid 1 on the one hand and iscoupled to a displacement device 30 on the other hand, in particular anX/Y displacement device or a rotary table. The displacement device 30effects a movement of the solid 1, whereby the latter can be moved in adefined manner with respect to the surrounding area and a laser optics,in particular a scanner.

FIG. 10d shows a further detailed schematic illustration of FIG. 10c .The round arrow inside the displacement device 30 identifies that thelatter can be rotated. Provision is further made between the solid 1 andthe cooling device 3 for a coupling layer, in particular an adhesivelayer. The coupling layer 30 is hereby preferably embodied in such a waythat it withstands a plurality of processing cylinders, in particularmore than 200 or more than 300 or more than 500 processing cycles, athigh mechanical and thermal stress. It can further be gathered from thisillustration that the laser beam source 401 preferably guides laserbeams along a first laser beam conductor 402 to an optics 40, from wherethe laser beams reach a scanner by means of a further laser beamconductor 403. In the alternative, however, it is also conceivablehereby that at least the laser beam source 401 and the scanner 400 areprovided.

FIG. 11 shows the cooling device 3. The cooling device 3 preferably hasa conducting-guiding structure, which is preferably formed by means of atool carrier, in particular a chuck. The conducting-guiding structurepreferably has a round basic shape. This advantageous, because animbalance can be avoided more easily with regard to spinning processes.The round basic shape is preferably further provided with flattenedportions 95-98. These flattened portions are advantageous, because theyallow or facilitate, respectively a coarse orientation and/or coffering.

The cooling device 3, in particular the conducting-guiding structure ofthe cooling device 3, preferably has a good thermal conductivity. Thecooling device 3 preferably further has anodized aluminum, wherebyabrasion particles are reduced or prevented, respectively. This isadvantageous, because the clean room compatibility is increased throughthis. The chuck is preferably further compatible for the detachingprocess.

Provision is preferably further made for at least two aligning elements65-68. The aligning elements 65-68 are preferably embodied as alignmentholes or slits or pins. The aligning elements 65-68 preferably formactuators for the non-positive and/or positive rotation transfer. Thealigning elements 65-68 preferably have steel or ceramic inserts,whereby a high wear resistance is attained. The aligning elements 65-68preferably serve the purpose of coupling the cooling device 3 to thedisplacement device 30.

Provision can further be made for aligning pins, they can be embodied asholding-down devices, e.g., whereby e.g. a force and/or positiveconnection to the conducting-guiding structure can be created.

Provision is preferably furthermore made for a notch, groove or marking76 on the cooling device 3. This feature is advantageous, because thesolid orientation, in particular ingot orientation, can be seen throughthis. The knowledge about the orientation of the solid, in particular ofthe ingot, can be used in order to be able to adapt the modifications 9,which are generated by means of the laser beams, to the crystallographicorientation.

Reference numeral 75 identifies an optional data carrier element and/ordata transfer element and/or data capturing element in a purelyexemplary manner. The element identified with reference numeral 75 ispreferably embodied as bar code and/or RFID element and/or SAW sensor.It in particular allows an integration into a manufacturing executionsystem (MES).

Cooling ducts for guiding a cooling fluid are preferably furtherprovided or embodied, respectively on or in the conducting-guidingstructure. The cooling duct or the cooling ducts 78 can serve thepurpose of controlling the temperature of the solid 1, of the coolingdevice 3 and/or of a machine holder, in particular the displacementdevice 30. Cooling fluid, in particular a liquid, can be supplied intothe cooling duct 78 via an inlet 77, and can be removed via an outlet79. The boundary surface or the coupling layer, respectively, betweensolid 1 and cooling device 3 preferably has a high thermal conductivity,in particular according to the thermal conductivity of the solid 1 or ofthe cooling device 3. In addition or in the alternative, the coolingdevice 3 can be cooled via the air interface. In the case of high speedsor displacement speeds, respectively, of the displacement device 30, theair layer, which forms around the cooling device 3, is very thin,whereby heat can be discharged very well.

An active temperature control is preferably furthermore integrated intothe MES. In addition or in the alterative, a process is monitored fordifferent substrate sizes and thicknesses.

A sealing of the fluid ducts in the case of a fixed storage preferablytakes place by means of pressing and, in the case of rotation, by meansof a central annular seal, e.g.

Reference numeral 69 identifies an optional sensor device, which ispreferably embodied as temperature sensor. Preferably, the sensor deviceis an SAW temperature sensor.

FIG. 12 shows the optics 40, 608, which is preferably used to generatethe modifications 9. The method according to the invention thuspreferably also comprises the step of providing an optics 40, 603,wherein the optics 608 preferably has at least two deflecting elements610, 612 for deflecting light beam portions 616, 618. The light beams616, 618 are preferably generated and emitted by the laser beam source401. The method according to the invention further preferably comprisesthe step or deflecting at least two light beam portions 616, 618, whichdiffer from one another, of the emitted light beam 606 by means of thedeflecting elements 610, 612, 613, wherein the light beam portions 616,618 are deflected in such a way that they penetrate into the solid 1 andwherein the deflected light beam portions 616, 618, which differ fromone another, meet in a focus 620 inside the solid 1 and the physicalmodification 9, in particular in the form of a grid defect, is generatedby means of the light beam portions 616, 618, which meet in the focus620, or the step of generating and emitting at least two light beams 606by means of the laser beam source or radiation source arrangement 401,respectively. The method according to the invention preferably furthercomprises the step of deflecting the light beams 606 by means of thedeflecting elements 610, 612, 613, wherein the light beams 606 aredeflected in such a way that they penetrate into the solid 1, andwherein the deflected light beams 606, which are different from oneanother, meet in a focus 620 inside the solid 1 and the physicalmodification 9, in particular in the form of a grid defect, is generatedby means of the light beams (6), which meet in the focus 620.

It is additionally conceivable that at least two light beam portions616, 618, which differ from one another, of at least one emitted lightbeam 606, in particular the light beam portions of a plurality ofemitted light beams, or the plurality of emitted light beams 606 aredeflected by means of the deflecting elements 610, 612, 613, wherein thelight beam portions 616, 618 or the light beams 606 are deflected insuch a way that they penetrate into the solid 1, and wherein thedeflected light beam portions 616, 618, which differ from one another,meet in a focus 620 inside the solid 1, and the physical modification 9,in particular in the form of a grid defect, is generated by means of thelight beam portions 616, 618 or light beams 606, which meet in the focus620.

According to the method according to the invention, at least two lightbeams 606 and preferably all light beams 606 can be split into lightbeam portions 616, 618, which differ from one another, in particularcover different paths, and which penetrate into the solid 1 at surfaceportions 622, 624, which are spaced apart from one another, of the solid1, in the case of a plurality of light beams 606, which are createdsynchronously, wherein the light beam portions 616, 186 of a respectivelight beam are deflected by means of deflecting elements 610, 612, 613,which differ from one another.

The optics 608 preferably has at least one light beam splitting means633, in particular a half mirror or beam splitter, and at least onelight beam 606 is split into at least two light beam portions 616, 618by means of at least the light beam splitting means 633. A light beam606 is preferably split into at least two light beam portions 616, 618by means of a light beam splitting means 633, in particular a halfmirror, wherein a light beam portion 616 is deflected by means of atleast two deflecting elements 610, 612, 613, in particular mirrors, insuch a way that it meets the other light beam portion 618 on the insideof the solid 1 in order to form a focus 620 for generating the physicalmodification 9. Particularly preferably, a plurality of physicalmodifications 9 is generated, wherein the physical modifications 9preferably form or describe, respectively, a plane and/or a contourand/or a silhouette and/or the outer shape of a body.

The at least one light beam 606 emitted by the laser beam source 901preferably consists of coherent light and the light waves of the lightbeam portions 616, 618, which meet in the focus 620, preferably have thesame phase and the same frequency.

Particularly preferably, at least one light beam portion 616, 618 or atleast one light beam 606 is deflected and focused by means of adeflecting element 610, 612, 613, which is embodied as parabolic mirror.

The at least one light beam portion 616, 618 or the at least one lightbeam 606 further preferably penetrates a deflecting element 610, 612,613, in particular the parabolic mirror, a beam forming device, inparticular a 1D telescope, in order to change the focus shape prior tothe deflection and focusing.

The laser beam source 401 preferably generates at least one or exactlytwo light beams, wherein the light beams 606 are generated as a functionof the band gap of the material of the solid 1 with different colors insuch a way that the modification 9 is generated by means of a two-photonprocess.

A first laser field is preferably formed by means of a first light beam606, wherein the first light beam 606 has photons comprising a firstenergy, and a second laser field is preferably formed by means of asecond light beam 606, wherein the second laser beam 606 has photonscomprising a second energy, wherein the first laser field is weaker thanthe second laser field and the first energy is larger than the secondenergy.

FIG. 13 shows the modification generation by means of two laser beams ortwo laser beam portions in a schematic illustration. The modifications 9hereby preferably have a vertical expansion of less than 50 μm andpreferably of less than 30 μm and particularly preferably of less than20 μm.

The focus 620 is preferably spaced apart from a penetration surface 626of the solid 1 by less than 1000 μm and preferably less than 500 μm andparticularly preferably less than 200 μm, wherein at least individuallight beam portions 616, 618 penetrate into the solid 1 via thepenetration surface 626 in order to generate the physical modification9.

The focus 620 is preferably generated in an overlapping portion of atleast two intersecting light beam portions 630, 632, wherein the lightbeam portions 630, 632 are generated by means of the light beam portions616, 618 or light beams 606.

What is thus described is a method for creating a detachment zone in asolid in order to detach a solid portion, especially a solid layer, fromthe solid, wherein the solid portion, which is to be detached, isthinner than the solid, from which the solid portion has been removed.The method according to the invention thereby preferably comprises atleast the steps of: providing a solid, which is to be processed, whereinthe solid is made of a chemical compound; providing a LASER lightsource; applying LASER radiation from the LASER light source to thesolid, wherein the laser beams penetrate into the solid via a surface ofthe solid portion, which is to be cut off, wherein the LASER radiationcontrols the temperature of a predefined portion of the solid inside thesolid in a defined manner such that a detachment zone or a plurality ofpartial detachment zones is formed, characterized in that thetemperature produced by the laser beams in a predefined portion of thesolid is so high that the material forming the predefined portion issubject to modifications in the form of a predetermined conversion ofmaterial.

What is further described is a method for creating a detachment zone ina solid in order to detach a solid portion from the solid, at leastcomprising the steps of: providing a solid, which is to be processed,wherein the solid is made of a chemical compound; providing a LASERlight source, applying LASER radiation from the LASER light source tothe solid, wherein the LASER radiation controls the temperature of apredefined portion of the solid inside the solid in a defined mannersuch that a detachment zone is formed, wherein the temperature producedin the predefined portion of the solid is so high that the materialforming the predefined portion is subject to a predetermined conversionof material.

LIST OF REFERENCE NUMERALS

-   1 solid-   2 detachment zone-   4 laser beam-   5 polished surface-   6 laser beam in the solid-   7 underside of the solid-   8 focus-   9 modification-   10 first solid-   11 solid layer-   12 second solid-   17 reference length-   18 main surface-   25 first crack portion-   27 second crack portion-   28 third crack portion-   29 fourth crack portion-   30 rotary table-   31 crack between outer edge and first modification block-   32 crack between two Modification blocks-   33 crack between outer edge and first modification block and further    modification block or outer edge-   34 crack between modification block and outer edge-   40 optics-   41 first zone without modification block-   42 second zone without modification block-   43 third zone without modification block-   44 fourth zone without modification block-   45 fifth zone without modification block-   51 unchanged material-   52 unchanged material-   53 Raman spectrum-   54 intensity in %-   56 wavelength in cm⁻¹-   61 graph relating to unchanged material portion-   62 graph relating to unchanged material portion-   65 first aligning element-   66 second aligning element-   67 third aligning element-   68 fourth alignment element-   69 sensor means-   75 data carrier element and/or data transfer element-   76 groove-   77 fluid inlet-   78 fluid line-   79 fluid outlet-   80 conducting-guiding structure-   71 first end of a crack portion-   72 second end of a crack portion-   91 first block of modifications-   92 second block of modifications-   112 second solid layer-   113 third solid layer-   140 receiving layer-   150 temperature control fluid-   161 deforming direction of the receiving layer-   300 coupling layer-   400 scanner-   401 laser beam source-   402 laser beam conductor-   403 further laser beam conductor-   501 exposed surface of the first solid layer-   502 laser penetration surface of the second solid layer-   503 exposed surface of the second solid layer-   504 laser penetration surface of the third solid layer-   505 exposed surface of the third solid layer-   606 light beam-   608 optics-   610 first deflecting element-   612 second deflecting element-   613 third deflecting element-   616 first light beam portion-   618 second light beam portion-   620 focus-   622 first surface portion-   624 second surface portion-   630 light beam portion-   632 light beam portion-   901 first field without modifications-   902 second field without modifications-   903 third field without modifications

1-15. (canceled)
 16. A method, comprising: directing laser light from alaser light source into a solid surface of a solid, the laser lightcontrolling a temperature of a predefined portion of the solid such thata detachment zone is formed in the solid, the temperature controlled bythe laser light subjecting a material of the solid which forms thepredefined portion to modifications which convert the material;arranging a receiving layer on the solid using a thermal applicationsuch that a crack expands in the solid along the detachment zone; andmoving the solid in a translational manner with respect to the laserlight source such that a number of the modifications per cm2 of thesolid surface per translational movement, through which the laser lightpenetrates into the solid to generate the modifications, is below apredefined maximum number, wherein a maximum number of the modificationsper cm2 and per the translational movement is determined as a functionof the material and of an energy density of the laser light.
 17. Themethod of claim 16, wherein the material of the solid is selected fromthe group consisting of a third, fourth and/or fifth main group of theperiodic table of elements and/or from the 12^(th) subgroup of theperiodic table of elements.
 18. The method of claim 16, furthercomprising: connecting the solid to a cooling device; and operating thecooling device during application of the laser light to the solid. 19.The method of claim 18, wherein the cooling device has at least onesensor device for capturing the temperature of the solid and, as afunction of a predefined temperature course, effects a cool-down of thesolid.
 20. The method of claim 18, further comprising: coupling thecooling device to a rotating means; and rotating the cooling device withthe solid arranged thereon by means of the rotating means duringgeneration of the modifications.
 21. The method of claim 16, wherein themodifications are generated with different patterns, in response toconsecutive rotations of the solid with respect to the laser lightsource.
 22. The method of claim 16, wherein the laser light source is alaser light scanner, and wherein generation of the modifications is afunction of a laser scanning direction of the laser light scanner, alaser polarization direction and crystal orientation of the material ofthe solid.
 23. The method of claim 16, wherein the distance betweencenters of two modifications, which are generated consecutively in amodification generating direction or in a circumferential direction ofthe solid is less than 10000 nm.
 24. The method of claim 16, wherein anouter limitation of the modifications, which are generated consecutivelyin a modification generating direction or in a circumferential directionof the solid, are spaced apart from one another by less than 10000 nm.25. The method of claim 16, wherein the number of generatedmodifications per cm² is different in at least two different zones ofthe solid, wherein a first block of modifications is generated in afirst zone and spaced apart from one another by less than 20 μm, whereina first partial detachment zone is formed by the first block ofmodifications, wherein a second block of modifications is generated in asecond zone and spaced apart from one another by less than 20 μm,wherein a second partial detachment zone is formed by the second blockof modifications, wherein the first zone and the second zone are spacedapart from one another by a third zone, wherein fewer modification ascompared to the first zone or the second zone per cm² are generated inthe third zone by means of the laser light, and wherein the first zoneis spaced apart from the second zone by more than 20 μm.
 26. The ofclaim 25, further comprising: generating the modifications at least inthe first block of modifications and in the second block ofmodifications in pulse intervals of between 0.01 μm and 10 μm, and/or inline spacings of between 0.01 μm and 20 μm, and/or at a pulse repetitionfrequency of between 16 kHz and 20 MHz.
 27. The method of claim 16,further comprising: providing an optics for guiding the laser light fromthe laser light source to the solid; and adapting the optics as afunction of the location at which a modification is generated, fromwhich at least one change of a numerical aperture of the optics iseffected, wherein the numerical aperture at a location in an edge zoneof the solid is smaller than at a different location of the solid, whichis located closer to a center of the solid.
 28. The method of claim 16,wherein the thermal application of the receiving layer comprises acool-down of the receiving layer to a temperature of below 20° C.
 29. Amethod, comprising: directing laser light from a laser light source intoa solid surface of a solid, the laser light controlling a temperature ofa predefined portion of the solid such that a detachment zone is formedin the solid, the temperature controlled by the laser light subjecting amaterial of the solid which forms the predefined portion tomodifications which convert the material; arranging a receiving layer onthe solid using a thermal application such that a crack expands in thesolid along the detachment zone and a solid portion separates from thesolid along the crack; and after the solid portion separates from thesolid along the crack, again directing laser light from the laser lightsource into the solid to control the temperature of additionalpredefined portion of the solid such that an additional detachment zoneis formed, the temperature subjecting a material of the additionalpredefined portion of the solid to a predetermined material conversion.30. The method of claim 29, further comprising: connecting the solid toa cooling device; and operating the cooling device during application ofthe laser light to the solid.
 31. The method of claim 30, wherein thecooling device has at least one sensor device for capturing thetemperature of the solid and, as a function of a predefined temperaturecourse, effects a cool-down of the solid.
 32. The method of claim 30,further comprising: coupling the cooling device to a rotating means; androtating the cooling device with the solid arranged thereon by means ofthe rotating means during generation of the modifications.
 33. A method,comprising: directing laser light from a laser light source into a solidsurface of a solid, the laser light controlling a temperature of apredefined portion of the solid such that a detachment zone is formed inthe solid, the temperature controlled by the laser light subjecting amaterial of the solid which forms the predefined portion tomodifications which convert the material; arranging a receiving layer onthe solid using a thermal application such that a crack expands in thesolid along the detachment zone and a solid portion separates from thesolid along the crack; and rotating or moving the solid in atranslational manner with respect to the laser light source, wherein adistance between centers of two modifications which are generatedconsecutively in a modification generating direction or in acircumferential direction of the solid is less than 10000 nm, and/or anouter limitation of the modifications which are generated consecutivelyin the modification generating direction or in the circumferentialdirection of the solid are spaced apart from one another by less than10000 nm.